US5198496A - Procedure for the obtention of thermoplastic elastomer mixtures - Google Patents

Procedure for the obtention of thermoplastic elastomer mixtures Download PDF

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Publication number
US5198496A
US5198496A US07/627,940 US62794090A US5198496A US 5198496 A US5198496 A US 5198496A US 62794090 A US62794090 A US 62794090A US 5198496 A US5198496 A US 5198496A
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United States
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weight
approximately
copolymers
mixtures
vinyl acetate
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US07/627,940
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English (en)
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Juan M. A. Alvarez
Eusebio F. Miron
Jose M. T. Lopez
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GIRSA SA de CV
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Repsol Quimica SA
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Assigned to REPSOL QUIMICA S.A., A CORP. OF SPAIN reassignment REPSOL QUIMICA S.A., A CORP. OF SPAIN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ALVAREZ, JUAN M.A., LOPEZ, JOSE M.T., MIRON, EUSEBIO F.
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Assigned to GIRSA, S.A. DE C.V. reassignment GIRSA, S.A. DE C.V. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: REPSOL QUIMICA, S.A.
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L53/00Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C08L53/02Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers of vinyl-aromatic monomers and conjugated dienes

Definitions

  • the object of the invention is a procedure for the production of partially reticulated thermoplastic elastomer mixtures, made up of at least two copolymers.
  • One of these copolymers is a block copolymer containing polymer blocks of a monoalkenylarene and a diene coupled together.
  • the second copolymer is a copolymer of ethylene and vinyl acetate (EVA copolymers).
  • Non reticulated mixtures of block copolymers of certain monoalkenylarenes and coupled dienes and of EVA copolymers are already known. Thus, in Off Plast. Caouthc., 1978, N.261, p.394-402 it is stated that it is possible to improve resistance to ozone, ultraviolet radiation, tearing and solvents of thermoplastic styrene and butadiene copolymers by incorporating to them certain types of EVA copolymers.
  • Various non reticulated mixtures of block copolymers of monoalkenylarenes and coupled dienes and EVA copolymers, useful in film manufacturing are described in U.S. Pat. Nos. 4,479,180, assigned to A. J. Wnuk on Oct.
  • thermoplastic block copolymers of monoalkenylarenes and coupled dienes and EVA copolymers with a content of the latter higher than about 15%, generally show a high resistance to ozone, they present the disadvantage of a lack of stability arising from the incompatibility of these two types of copolymers.
  • compositions obtained according to our invention are that, in spite of the mixtures being partially reticulated, they can be processed and reprocessed by the conventional techniques for the transformation of thermoplastic materials, such as extrusion, moulding by injection, moulding by compression, etc. The residues or trimmings can be reprocessed.
  • dynamic vulcanization is performed either during the mixing of the ingredients at a suitable temperature, in equipment such as roller mills, Banbury mixers, continuous mixers and in extrusion presses, for example, in double spindle extrusion presses, or alternatively on the mixture previously prepared in the aforementioned types of equipment.
  • the dynamic vulcanization of the mixtures of thermoplastic block copolymers of coupled monoalkenylarenes and dienes with EVA copolymers is achieved within the framework of the invention by using free radical generating agents, such as for example, organic peroxides, which can be aromatic or aliphatic, for example aromatic diacylic peroxides and aliphatic diacylit peroxides, dibasic acid peroxides, ketone peroxides, alkyl peroxyethers, alkyl hydroperoxides such as diacetyl peroxide, di-benzoyl peroxide, bis 2,4-dichlorobenzoyl peroxide, di-tercbutyl peroxide, tercbutyl perbenzoate, tercbutylamyl peroxide, 1,3-bis(terc-butylperoxyisopropyl) cumene, dilauroyl peroxide, succinic acid peroxide, cyclohexanone peroxide,
  • vulcanizing agents are azides, such as azidoformiates and aromatic polyazides.
  • thermoplastic block copolymers of coupled monoalkenylarenes and dienes with EVA copolymers is carried out in bulk (internal mixing cylinder train, extrusion press).
  • the conditions for reticulation are selected in such a way as to ensure that the presence of gel in the mixture is not so high that it causes the mixture to lose its thermoplastic nature.
  • the duration of the mixing operation must be enough to ensure the full decomposition of the radical-generating agent, since otherwise its presence in the final mixture might give rise to problems during further processing.
  • the optimum values for the above mentioned parameters may be easily determined by means of prior trials, as is well known by the experts.
  • the degree of reticulation can be measured by determining the content of gels insoluble in chlorobenzene, chloroform, etc.
  • the mixing temperature must be sufficiently high to allow the proper flow of the constituents of the mixture, and will logically depend on the nature of the copolymers used. As a rule, the mixing temperature mudt be within the approximate limits of 125 and 250 deg. C., and preferably between 150 and 200 degrees C. The upper limit is imposed by, the need to avoid any degradation of the substance during the mixing-reticulation process.
  • the selection of the radical-generating agent must be made taking into account its mean lifetime value at the mixing temperature, as is well known by the experts.
  • the mixtures, according to the invention contain 95-60% by weight of thermoplastic block copolymers of coupled monoalkenylarenes and dienes and 5-40% by weight of EVA copolymer.
  • thermoplastic block copolymers whose use is recommended in the present invention are known substances having polymeric blocks of monoalkenylarenes and polymeric blocks of diene coupled together.
  • the blocks must be arranged such that there exist at least two polymeric end blocks of monoalkenylarenes A and at least a middle elastomeric block of coupled diene D.
  • the polymeric block of monoalkenylarene must make up approximately between 8 and 55% by weight of the block copolymer.
  • the molecular weight of the copolymer must be such that its Flow rate, determined by the ASTM D 1238 method "Standard Tex Method for Flow Rates of Thermoplastics by Extrusion Plastomer", (condition E) is higher than 0.01.
  • the monoalkenylarene block polymer favoured is polystyrene and the coupled diene polymers favoured are polybutadienes and polyisoprenes, with polubutadienes enjoying special favour.
  • the preferred thermoplastic block copolymers are radial or star copolymers.
  • the EVA copolymers which can be used in within the framework of the present invention are linear copolymers with a random distribution of ethylene and vinyl acetate units.
  • the EVA copolymers must contain between 5 and 50% by weight and preferably between 15 and 35% by weight of vinyl acetate.
  • Their molecular weight must be such that the flow rate lies between approximately 0.1 and 50 and preferably between 0.1 and 10 (values determined by method ASTM D 1238, condition B).
  • the mixtures covered by the present invention may contain other additional constituents, added to same in order to achieve some specific improvement of their properties or simply with the aim of reducing their cost.
  • they may for instance contain fillers and strengtheners such as calcium carbonate, calcium sulphate, coal-black, clay, silica, magnesium oxide, zinc oxide, alumina talcum, glass powder, glass fibre, etc, both in the presence and in the absence compatibilizing agents.
  • fillers and strengtheners such as calcium carbonate, calcium sulphate, coal-black, clay, silica, magnesium oxide, zinc oxide, alumina talcum, glass powder, glass fibre, etc, both in the presence and in the absence compatibilizing agents.
  • antistatic agents such as atoxylated amines or quaternary ammonium salts with organic substitutes containing 12-18 atoms of carbon.
  • processing lubricants known in the art.
  • stabilizing additives against the heat and antioxidant are organic phosphites and other organic substances such as trihydroxybutyrophene.
  • primary antioxidant additives which can be used in the mixtures covered by the present invention are ester-inhibited phenols (e.g. 2,6-ditertbutyl-pcresol) and several types of aromatic amines. It is possible to use secondary antioxidant additives derived from thiodipropionic acid or aromatic phosphites.
  • the stabilizing additives against heat and antioxidants should be added to the mixtures at levels between 0.01 and 2% by weight.
  • the degradation of the mixtures covered by the present invention upon exposure to ultraviolet light can be reduced below the intrinsical levels by adding photostabilizers.
  • photostabilizers are those derived from benzophenone. Said photostabilizers should be added to the mixture at levels between 0.01 and 3% by weight.
  • pigments may be added to give them a specific colour.
  • Pigments are added generally to the mixtures in the form of concentrates in order to ensure a better dispersion of the pigments, generally the pigments are used at levels ranging between 0.5-4% by weight.
  • thermoplastic materials covered by the present invention may be used for a broad range of applications requiring thermoplastic materials resistant to ozone, with good elastic properties and great stability.
  • EVA copolymer Pa 440 produced by Repsol Quimica S.A. (a copolymer of ethylene and vinyl acetate containing 28% vinyl acetate, flow rate according to ASTM D 1238 equal to 6 g/10 min) and a Calprene 416 rubber (star block copolymer of styrene and butadiene, 25% styrene, 75% butadiene, flow rate equal to 0.5 g/10 min.) manufactured by Repsol Quimica S.A.
  • Repsol Quimica S.A. a copolymer of ethylene and vinyl acetate containing 28% vinyl acetate, flow rate according to ASTM D 1238 equal to 6 g/10 min
  • Calprene 416 rubber star block copolymer of styrene and butadiene, 25% styrene, 75% butadiene, flow rate equal to 0.5 g/10 min.
  • the continuous extrusion press was fed with 4 Kg/h of Calprene 416, 1 Kg/h of EVA copolymer PA 440, and 0.11% by weight of a free radical generating agent (PerKadox 1440, bis (terbutyl-peroxy-isopropyl) benzene, manufactured by AKZO).
  • the mixing temperature was 180 deg. C.
  • the mixture thus obtained was subjected to 4 successive extrusions in order to study its stability and the evolution of its properties upon being reprocessed.
  • the extrusions were carried out under the same conditions as the mixing.
  • Table 1 shows the variation in the toughness of the mixture subjected to the various extrusions. For the purposes of comparison it also includes the toughness values obtained by extruding under the same conditions a mixture of the same composition but prepared in accordance with prior methods, that is, omitting the addition of the free radical generating agent.
  • Table 2 concludes the results of tests measuring resistance to compression, carried out according to the ASTM 395 standard at 23 deg. C.
  • the tests consisted of subjecting the sample to a 20% and 25% deformation for 72 hours and evaluating the degree of remaining deformation after such a treatment.
  • Table 3 shows the values of the resistance to abrasion of the samples prepared in accordance with the invention. For the purposes of comparison a conventional mixture is included prepared under the same conditions, but omitting the addition of peroxide.
  • Table 3 shows the improvements regarding resistance to abrasion which can be achieved by preparing the mixtures of SBS and EVA copolymers by dynamic vulcanization, in accordance with the process which is the subject of the invention.
  • a mixture was prepared of an SBS rubber and an EVA copolymer in accordance with the procedure described in example No. 1, but substituting EVA copolymer PA 440 (28% by weight of vinyl acetate, flow rate condition B, 6 g/10 min) by an EVA copolymer PA 410 (18% vinyl acetate, flow rate 150) whose flow rate is outside the limits claimed in the present invention.
  • Table 4 shows the results of a test for resistance to ozone, according to ASTM-2240 standard, of the mixture obtained. For comparison purposes the results obtained with the mixture from example 1, prepared according to the invention, are included.
  • test tubes prepared with the mixture from example 1 did not show any cracks, whereas the test tubes from example 3 (comparison) suffered destructive effects of catastrophic proportions.

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
US07/627,940 1989-12-14 1990-12-13 Procedure for the obtention of thermoplastic elastomer mixtures Expired - Lifetime US5198496A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ESP8904216 1989-12-14
ES8904216A ES2019755A6 (es) 1989-12-14 1989-12-14 Procedimiento de obtencion de mezclas termoplasticas elastomericas.

Publications (1)

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US5198496A true US5198496A (en) 1993-03-30

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US (1) US5198496A (de)
EP (1) EP0433210B1 (de)
AT (1) ATE137250T1 (de)
DE (1) DE69026692T2 (de)
ES (1) ES2019755A6 (de)
MX (1) MX173035B (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5691052A (en) * 1995-06-07 1997-11-25 American National Can Company Polymeric compositions with high self-adhesion and packaging materials and packages made therefrom
US6408593B1 (en) * 1999-09-01 2002-06-25 Pete Foster Shingle composition
WO2010024640A3 (ko) * 2008-08-29 2010-06-24 (주)엘지하우시스 시트 조성물 및 이것으로부터 제조된 시트

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9023367D0 (en) * 1990-10-26 1990-12-05 Draftex Ind Ltd Thermoplastic materials and products
FR2730242B1 (fr) * 1995-02-08 1997-04-25 Chaignaud Ind Composition thermoplastique et procede de preparation

Citations (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3562356A (en) * 1965-09-24 1971-02-09 Shell Oil Co Block copolymer blends with certain ethylene-unsaturated ester copolymers
US3562355A (en) * 1968-03-20 1971-02-09 Shell Oil Co Block copolymer blends with certain polyurethanes or ethylene-unsaturated ester copolymers
US3576911A (en) * 1969-03-27 1971-04-27 Goodyear Tire & Rubber Shoe sole compound
US4208315A (en) * 1979-02-01 1980-06-17 Shell Oil Company Footwear composition of a blend of ethylene-vinyl acetate copolymer, poly(vinyl chloride) and a block copolymer
US4216131A (en) * 1979-05-04 1980-08-05 Shell Oil Company Smooth-look footwear composition
US4234636A (en) * 1978-12-28 1980-11-18 Phillips Petroleum Company Thermoplastic elastomeric composition, product and method of manufacture
US4377658A (en) * 1982-01-22 1983-03-22 Shell Oil Company Solvent resistant polymeric composition
US4476180A (en) * 1983-02-01 1984-10-09 The Procter & Gamble Company Nonblocking elastomeric polymer blends of ABA block copolymer and ethylene-vinyl acetate copolymer
US4593062A (en) * 1984-12-10 1986-06-03 Exxon Research & Engineering Co. Dynamically cured thermoplastic olefin polymers
US4607074A (en) * 1984-07-11 1986-08-19 Exxon Research & Engineering Co. Dynamically cured thermoplastic olefin polymers
US4627472A (en) * 1978-07-31 1986-12-09 Monsanton Company Hose reinforced with discontinuous fibers oriented in the radial direction
US4639487A (en) * 1984-07-11 1987-01-27 Exxon Research & Engineering Co. Heat shrinkable thermoplastic olefin composition
US4851468A (en) * 1984-12-10 1989-07-25 Exxon Research & Engineering Company Dynamically cured thermoplastic olefin polymers
US4894408A (en) * 1988-08-23 1990-01-16 Exxon Chemical Patents Inc. Thermoplastic olefin compositions of EPDM rubber and ethylene copolymer resin
US4960830A (en) * 1984-07-11 1990-10-02 Exxon Research And Engineering Company Dynamically cured thermoplastic olefin polymers
US5037888A (en) * 1989-11-09 1991-08-06 Eastman Kodak Company Thermoplastic elastomeric compositions and method for their preparation
US5086121A (en) * 1984-07-11 1992-02-04 Advanced Elastomer Systems, L. P. Dynamically cured thermoplastic olefin polymers

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IT630983A (de) * 1959-06-03
US3806558A (en) * 1971-08-12 1974-04-23 Uniroyal Inc Dynamically partially cured thermoplastic blend of monoolefin copolymer rubber and polyolefin plastic
JPS59108047A (ja) * 1982-12-13 1984-06-22 Kazuo Saotome 熱可塑性エラストマ−組成物
JPS62288647A (ja) * 1986-06-06 1987-12-15 Japan Synthetic Rubber Co Ltd 重合体架橋物
JPH02173020A (ja) * 1988-12-26 1990-07-04 Mitsui Toatsu Chem Inc 結晶性スチレン系ブロック共重合樹脂の製造方法

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US3562356A (en) * 1965-09-24 1971-02-09 Shell Oil Co Block copolymer blends with certain ethylene-unsaturated ester copolymers
US3562355A (en) * 1968-03-20 1971-02-09 Shell Oil Co Block copolymer blends with certain polyurethanes or ethylene-unsaturated ester copolymers
US3576911A (en) * 1969-03-27 1971-04-27 Goodyear Tire & Rubber Shoe sole compound
US4627472A (en) * 1978-07-31 1986-12-09 Monsanton Company Hose reinforced with discontinuous fibers oriented in the radial direction
US4234636A (en) * 1978-12-28 1980-11-18 Phillips Petroleum Company Thermoplastic elastomeric composition, product and method of manufacture
US4208315A (en) * 1979-02-01 1980-06-17 Shell Oil Company Footwear composition of a blend of ethylene-vinyl acetate copolymer, poly(vinyl chloride) and a block copolymer
US4216131A (en) * 1979-05-04 1980-08-05 Shell Oil Company Smooth-look footwear composition
US4377658A (en) * 1982-01-22 1983-03-22 Shell Oil Company Solvent resistant polymeric composition
US4476180A (en) * 1983-02-01 1984-10-09 The Procter & Gamble Company Nonblocking elastomeric polymer blends of ABA block copolymer and ethylene-vinyl acetate copolymer
US4845145A (en) * 1984-07-11 1989-07-04 Exxon Research & Engineering Company Dynamically cured thermoplastic olefin polymers
US4607074A (en) * 1984-07-11 1986-08-19 Exxon Research & Engineering Co. Dynamically cured thermoplastic olefin polymers
US4639487A (en) * 1984-07-11 1987-01-27 Exxon Research & Engineering Co. Heat shrinkable thermoplastic olefin composition
US4960830A (en) * 1984-07-11 1990-10-02 Exxon Research And Engineering Company Dynamically cured thermoplastic olefin polymers
US5086121A (en) * 1984-07-11 1992-02-04 Advanced Elastomer Systems, L. P. Dynamically cured thermoplastic olefin polymers
US4593062A (en) * 1984-12-10 1986-06-03 Exxon Research & Engineering Co. Dynamically cured thermoplastic olefin polymers
US4851468A (en) * 1984-12-10 1989-07-25 Exxon Research & Engineering Company Dynamically cured thermoplastic olefin polymers
US4894408A (en) * 1988-08-23 1990-01-16 Exxon Chemical Patents Inc. Thermoplastic olefin compositions of EPDM rubber and ethylene copolymer resin
US5037888A (en) * 1989-11-09 1991-08-06 Eastman Kodak Company Thermoplastic elastomeric compositions and method for their preparation

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Concise Chemical and Technical Dictionary pp. 978-979, Chem. Pub. Co., Inc. 1947 Brooklyn, N.Y.

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5691052A (en) * 1995-06-07 1997-11-25 American National Can Company Polymeric compositions with high self-adhesion and packaging materials and packages made therefrom
US6408593B1 (en) * 1999-09-01 2002-06-25 Pete Foster Shingle composition
WO2010024640A3 (ko) * 2008-08-29 2010-06-24 (주)엘지하우시스 시트 조성물 및 이것으로부터 제조된 시트
US20110159254A1 (en) * 2008-08-29 2011-06-30 Sang-Deuk Choi Sheet composition and sheet produced from same
US8853328B2 (en) 2008-08-29 2014-10-07 Lg Hausys, Ltd. Sheet composition and sheet produced from same

Also Published As

Publication number Publication date
EP0433210B1 (de) 1996-04-24
DE69026692D1 (de) 1996-05-30
EP0433210A3 (en) 1992-04-22
EP0433210A2 (de) 1991-06-19
ATE137250T1 (de) 1996-05-15
DE69026692T2 (de) 1996-11-28
MX173035B (es) 1994-01-28
ES2019755A6 (es) 1991-07-01

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